Announcing My Autofocus Test Chart
http://regex.info/blog/
Nikon D200 + Nikkor 17-55 f/2.8 @ 55mm — 1/1250 sec, f/2.8, ISO 400 — full exif

During the three-month ordeal of autofocus problems with my Nikkor 70-200 f/2.8 zoom, between suspecting a problem and finally having it fixed by Nikon, I learned a lot about SLR autofocus — how it works, and how best to test it.

There are plenty of autofocus test charts available on the web, but all of them were severely deficient in one way or another, so I ended up making my own. Its development progressed over time as I tried different approaches, discarding what didn't work and refining what did. (The chart I used in November shows elements of both.)

After Nikon finally fixed my equipment and I was able to retest it with the final version of the chart, I was pleased not only with how well my equipment worked, but also with how easily and confidently my chart allowed me to confirm it.

So, I'm finally ready to release my chart, with copious and verbose instructions on how to use it, as another of my photography-tech posts:

Jeffrey's Autofocus Test Chart

If you at all suspect you have autofocus issues with your lens or you body, I encourage you to check it out.

Some of my other photography-tech posts are highlighted in the box at right.



All 2 comments so far, oldest first...

Thanks !

— comment by Arnaud on January 24th, 2007 at 1:33am JST (17 years, 2 months ago) comment permalink

Jeffrey,

Your technical analysis and experience – and your sharing of it – has been quite helpful!

I suspect that I should send my newly purchased 70-200 2.8 VR to Nikon Service…. I will suffer some… having made the purchase just very recently and not wanting to be “separated from” my “new” lens…. and having to accept that I should have spent a “few” dollars more and purchased the lens new rather than used through eBay….. There is some comfort though in knowing from your sharing that I might have experienced “issues” even if I had purchased a “New” lens.

Perhaps you have covered it, but I did not see “testing” to evaluate the “VR” functioning. Have you also developed a “Test Procedure” for that?

Thank You,
Dan Robinson

I’ve not thought about a test for the VR, but you should be able to clearly notice the difference in the viewfinder when it’s active. —Jeffrey

— comment by Dan Robinson on February 26th, 2013 at 4:41pm JST (11 years, 1 month ago) comment permalink
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